Future Policy Benefits and Claims - Interest Accretion and Current Discount Rates (Details)	Sep. 30, 2025	Dec. 31, 2024
Retirement and Income Solutions \| Pension risk transfer
Future Policy Benefits and Claims
Interest accretion rate	4.68%	4.61%
Current discount rate	5.20%	5.55%
Retirement and Income Solutions \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.22%	4.22%
Current discount rate	5.11%	5.50%
Principal Asset Management \| International Pension \| Latin America \| Individual fixed income annuities
Future Policy Benefits and Claims
Interest accretion rate	4.20%	4.21%
Current discount rate	2.92%	3.04%
Benefits and Protection \| Specialty Benefits \| Individual disability
Future Policy Benefits and Claims
Interest accretion rate	3.85%	3.89%
Current discount rate	5.34%	5.64%
Benefits and Protection \| Life Insurance \| Universal life
Future Policy Benefits and Claims
Interest accretion rate	4.74%	4.75%
Benefits and Protection \| Life Insurance \| Term life
Future Policy Benefits and Claims
Interest accretion rate	4.83%	4.82%
Current discount rate	4.90%	5.35%
Corporate \| Long-term care insurance
Future Policy Benefits and Claims
Interest accretion rate	6.16%	6.16%
Current discount rate	5.28%	5.58%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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